main/xen: main/xen: fix xsa45 and xsa58 (CVE-2013-1918,CVE-2013-1432)

ref #2123
fixes #2127

3 files changed, 1237 insertions, 1 deletions

diff --git a/main/xen/APKBUILD b/main/xen/APKBUILD
index 4f44f4d0a6..4d95a09909 100644
--- a/main/xen/APKBUILD
+++ b/main/xen/APKBUILD
@@ -2,7 +2,7 @@
 # Maintainer: William Pitcock <nenolod@dereferenced.org>
 pkgname=xen
 pkgver=4.1.4
-pkgrel=5
+pkgrel=6
 pkgdesc="Xen hypervisor"
 url="http://www.xen.org/"
 arch="x86 x86_64"
@@ -23,12 +23,14 @@ source="http://bits.xensource.com/oss-xen/release/$pkgver/$pkgname-$pkgver.tar.g
 	busybox-sed.patch
 	xsa33-4.1.patch
 	xsa41.patch
+	xsa45-4.1.patch
 	xsa52-4.1.patch
 	xsa53-4.1.patch
 	xsa54.patch
 	xsa55-4.1.patch
 	xsa56.patch
 	xsa57-4.1.patch
+	xsa58-4.1.patch
 
 	xencommons.initd
 	xend.initd
@@ -106,12 +108,14 @@ fa06495a175571f4aa3b6cb88937953e  librt.patch
 1bea3543ddc712330527b62fd9ff6520  busybox-sed.patch
 25ba4efc5eee29daa12855fbadce84f8  xsa33-4.1.patch
 ce56f00762139cd611dfc3332b7571cf  xsa41.patch
+09c675a4a28ee00dd9abeacc07426edd  xsa45-4.1.patch
 db1e5a92547c8c8ed2e1872efed99ab0  xsa52-4.1.patch
 e11ae888997d11fcb91b431ebf609d4e  xsa53-4.1.patch
 a8393d1ec6b886ea72ffe624a04ee10a  xsa54.patch
 391d90e3851df0b42b2971e8b860e19a  xsa55-4.1.patch
 e70b9128ffc2175cea314a533a7d8457  xsa56.patch
 a065178b8f5ed028b97fa51db97e41e2  xsa57-4.1.patch
+dd46795cf7bb7bb9baa50bfdf4813d4f  xsa58-4.1.patch
 0b62c1fbe2699a32e745724fd301db5b  xencommons.initd
 5ee6a16ec70dfbcd4944ded71b393fa2  xend.initd
 a2b5234483f1b5892d22e9315d9c307f  xendomains.initd"
diff --git a/main/xen/xsa45-4.1.patch b/main/xen/xsa45-4.1.patch
new file mode 100644
index 0000000000..6dbf1f4456
--- /dev/null
+++ b/main/xen/xsa45-4.1.patch
@@ -0,0 +1,1113 @@
+diff --git a/xen/arch/x86/domain.c b/xen/arch/x86/domain.c
+index 4009a60..9a34488 100644
+--- a/xen/arch/x86/domain.c
++++ b/xen/arch/x86/domain.c
+@@ -70,8 +70,6 @@ void (*dead_idle) (void) __read_mostly = default_dead_idle;
+ static void paravirt_ctxt_switch_from(struct vcpu *v);
+ static void paravirt_ctxt_switch_to(struct vcpu *v);
+ 
+-static void vcpu_destroy_pagetables(struct vcpu *v);
+-
+ static void continue_idle_domain(struct vcpu *v)
+ {
+     reset_stack_and_jump(idle_loop);
+@@ -678,6 +676,7 @@ int arch_set_info_guest(
+ {
+     struct domain *d = v->domain;
+     unsigned long cr3_pfn = INVALID_MFN;
++    struct page_info *cr3_page;
+     unsigned long flags, cr4;
+     int i, rc = 0, compat;
+ 
+@@ -817,72 +816,103 @@ int arch_set_info_guest(
+     if ( rc != 0 )
+         return rc;
+ 
++    set_bit(_VPF_in_reset, &v->pause_flags);
++
+     if ( !compat )
+-    {
+         cr3_pfn = gmfn_to_mfn(d, xen_cr3_to_pfn(c.nat->ctrlreg[3]));
++#ifdef __x86_64__
++    else
++        cr3_pfn = gmfn_to_mfn(d, compat_cr3_to_pfn(c.cmp->ctrlreg[3]));
++#endif
++    cr3_page = mfn_to_page(cr3_pfn);
+ 
+-        if ( !mfn_valid(cr3_pfn) ||
+-             (paging_mode_refcounts(d)
+-              ? !get_page(mfn_to_page(cr3_pfn), d)
+-              : !get_page_and_type(mfn_to_page(cr3_pfn), d,
+-                                   PGT_base_page_table)) )
+-        {
+-            destroy_gdt(v);
+-            return -EINVAL;
+-        }
++    if ( !mfn_valid(cr3_pfn) || !get_page(cr3_page, d) )
++    {
++        cr3_page = NULL;
++        rc = -EINVAL;
++    }
++    else if ( paging_mode_refcounts(d) )
++        /* nothing */;
++    else if ( cr3_page == v->arch.old_guest_table )
++    {
++        v->arch.old_guest_table = NULL;
++        put_page(cr3_page);
++    }
++    else
++    {
++        /*
++         * Since v->arch.guest_table{,_user} are both NULL, this effectively
++         * is just a call to put_old_guest_table().
++         */
++        if ( !compat )
++            rc = vcpu_destroy_pagetables(v);
++        if ( !rc )
++            rc = get_page_type_preemptible(cr3_page,
++                                           !compat ? PGT_root_page_table
++                                                   : PGT_l3_page_table);
++        if ( rc == -EINTR )
++            rc = -EAGAIN;
++    }
+ 
++    if ( rc )
++        /* handled below */;
++    else if ( !compat )
++    {
+         v->arch.guest_table = pagetable_from_pfn(cr3_pfn);
+ 
+ #ifdef __x86_64__
+         if ( c.nat->ctrlreg[1] )
+         {
+             cr3_pfn = gmfn_to_mfn(d, xen_cr3_to_pfn(c.nat->ctrlreg[1]));
++            cr3_page = mfn_to_page(cr3_pfn);
+ 
+-            if ( !mfn_valid(cr3_pfn) ||
+-                 (paging_mode_refcounts(d)
+-                  ? !get_page(mfn_to_page(cr3_pfn), d)
+-                  : !get_page_and_type(mfn_to_page(cr3_pfn), d,
+-                                       PGT_base_page_table)) )
++            if ( !mfn_valid(cr3_pfn) || !get_page(cr3_page, d) )
+             {
+-                cr3_pfn = pagetable_get_pfn(v->arch.guest_table);
+-                v->arch.guest_table = pagetable_null();
+-                if ( paging_mode_refcounts(d) )
+-                    put_page(mfn_to_page(cr3_pfn));
+-                else
+-                    put_page_and_type(mfn_to_page(cr3_pfn));
+-                destroy_gdt(v);
+-                return -EINVAL;
++                cr3_page = NULL;
++                rc = -EINVAL;
++            }
++            else if ( !paging_mode_refcounts(d) )
++            {
++                rc = get_page_type_preemptible(cr3_page, PGT_root_page_table);
++                switch ( rc )
++                {
++                case -EINTR:
++                    rc = -EAGAIN;
++                case -EAGAIN:
++                    v->arch.old_guest_table =
++                        pagetable_get_page(v->arch.guest_table);
++                    v->arch.guest_table = pagetable_null();
++                    break;
++                }
+             }
+ 
+-            v->arch.guest_table_user = pagetable_from_pfn(cr3_pfn);
++            if ( !rc )
++                v->arch.guest_table_user = pagetable_from_pfn(cr3_pfn);
+         }
+         else if ( !(flags & VGCF_in_kernel) )
+         {
+-            destroy_gdt(v);
+-            return -EINVAL;
++            cr3_page = NULL;
++            rc = -EINVAL;
+         }
+     }
+     else
+     {
+         l4_pgentry_t *l4tab;
+ 
+-        cr3_pfn = gmfn_to_mfn(d, compat_cr3_to_pfn(c.cmp->ctrlreg[3]));
+-
+-        if ( !mfn_valid(cr3_pfn) ||
+-             (paging_mode_refcounts(d)
+-              ? !get_page(mfn_to_page(cr3_pfn), d)
+-              : !get_page_and_type(mfn_to_page(cr3_pfn), d,
+-                                   PGT_l3_page_table)) )
+-        {
+-            destroy_gdt(v);
+-            return -EINVAL;
+-        }
+-
+         l4tab = __va(pagetable_get_paddr(v->arch.guest_table));
+         *l4tab = l4e_from_pfn(
+             cr3_pfn, _PAGE_PRESENT|_PAGE_RW|_PAGE_USER|_PAGE_ACCESSED);
+ #endif
+     }
++    if ( rc )
++    {
++        if ( cr3_page )
++            put_page(cr3_page);
++        destroy_gdt(v);
++        return rc;
++    }
++
++    clear_bit(_VPF_in_reset, &v->pause_flags);
+ 
+     if ( v->vcpu_id == 0 )
+         update_domain_wallclock_time(d);
+@@ -904,17 +934,16 @@ int arch_set_info_guest(
+ #undef c
+ }
+ 
+-void arch_vcpu_reset(struct vcpu *v)
++int arch_vcpu_reset(struct vcpu *v)
+ {
+     if ( !is_hvm_vcpu(v) )
+     {
+         destroy_gdt(v);
+-        vcpu_destroy_pagetables(v);
+-    }
+-    else
+-    {
+-        vcpu_end_shutdown_deferral(v);
++        return vcpu_destroy_pagetables(v);
+     }
++
++    vcpu_end_shutdown_deferral(v);
++    return 0;
+ }
+ 
+ /* 
+@@ -1917,63 +1946,6 @@ static int relinquish_memory(
+     return ret;
+ }
+ 
+-static void vcpu_destroy_pagetables(struct vcpu *v)
+-{
+-    struct domain *d = v->domain;
+-    unsigned long pfn;
+-
+-#ifdef __x86_64__
+-    if ( is_pv_32on64_vcpu(v) )
+-    {
+-        pfn = l4e_get_pfn(*(l4_pgentry_t *)
+-                          __va(pagetable_get_paddr(v->arch.guest_table)));
+-
+-        if ( pfn != 0 )
+-        {
+-            if ( paging_mode_refcounts(d) )
+-                put_page(mfn_to_page(pfn));
+-            else
+-                put_page_and_type(mfn_to_page(pfn));
+-        }
+-
+-        l4e_write(
+-            (l4_pgentry_t *)__va(pagetable_get_paddr(v->arch.guest_table)),
+-            l4e_empty());
+-
+-        v->arch.cr3 = 0;
+-        return;
+-    }
+-#endif
+-
+-    pfn = pagetable_get_pfn(v->arch.guest_table);
+-    if ( pfn != 0 )
+-    {
+-        if ( paging_mode_refcounts(d) )
+-            put_page(mfn_to_page(pfn));
+-        else
+-            put_page_and_type(mfn_to_page(pfn));
+-        v->arch.guest_table = pagetable_null();
+-    }
+-
+-#ifdef __x86_64__
+-    /* Drop ref to guest_table_user (from MMUEXT_NEW_USER_BASEPTR) */
+-    pfn = pagetable_get_pfn(v->arch.guest_table_user);
+-    if ( pfn != 0 )
+-    {
+-        if ( !is_pv_32bit_vcpu(v) )
+-        {
+-            if ( paging_mode_refcounts(d) )
+-                put_page(mfn_to_page(pfn));
+-            else
+-                put_page_and_type(mfn_to_page(pfn));
+-        }
+-        v->arch.guest_table_user = pagetable_null();
+-    }
+-#endif
+-
+-    v->arch.cr3 = 0;
+-}
+-
+ int domain_relinquish_resources(struct domain *d)
+ {
+     int ret;
+@@ -1992,7 +1964,9 @@ int domain_relinquish_resources(struct domain *d)
+         for_each_vcpu ( d, v )
+         {
+             /* Drop the in-use references to page-table bases. */
+-            vcpu_destroy_pagetables(v);
++            ret = vcpu_destroy_pagetables(v);
++            if ( ret )
++                return ret;
+ 
+             /*
+              * Relinquish GDT mappings. No need for explicit unmapping of the
+diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c
+index 9f53728..140e70c 100644
+--- a/xen/arch/x86/hvm/hvm.c
++++ b/xen/arch/x86/hvm/hvm.c
+@@ -3083,8 +3083,11 @@ static void hvm_s3_suspend(struct domain *d)
+ 
+     for_each_vcpu ( d, v )
+     {
++        int rc;
++
+         vlapic_reset(vcpu_vlapic(v));
+-        vcpu_reset(v);
++        rc = vcpu_reset(v);
++        ASSERT(!rc);
+     }
+ 
+     vpic_reset(d);
+diff --git a/xen/arch/x86/hvm/vlapic.c b/xen/arch/x86/hvm/vlapic.c
+index 3af41cc..8d47bd0 100644
+--- a/xen/arch/x86/hvm/vlapic.c
++++ b/xen/arch/x86/hvm/vlapic.c
+@@ -252,10 +252,13 @@ static void vlapic_init_sipi_action(unsigned long _vcpu)
+     {
+     case APIC_DM_INIT: {
+         bool_t fpu_initialised;
++        int rc;
++
+         domain_lock(target->domain);
+         /* Reset necessary VCPU state. This does not include FPU state. */
+         fpu_initialised = target->fpu_initialised;
+-        vcpu_reset(target);
++        rc = vcpu_reset(target);
++        ASSERT(!rc);
+         target->fpu_initialised = fpu_initialised;
+         vlapic_reset(vcpu_vlapic(target));
+         domain_unlock(target->domain);
+diff --git a/xen/arch/x86/mm.c b/xen/arch/x86/mm.c
+index 30d281d..ceeb998 100644
+--- a/xen/arch/x86/mm.c
++++ b/xen/arch/x86/mm.c
+@@ -1182,7 +1182,16 @@ static int put_page_from_l3e(l3_pgentry_t l3e, unsigned long pfn,
+ #endif
+ 
+     if ( unlikely(partial > 0) )
++    {
++        ASSERT(preemptible >= 0);
+         return __put_page_type(l3e_get_page(l3e), preemptible);
++    }
++
++    if ( preemptible < 0 )
++    {
++        current->arch.old_guest_table = l3e_get_page(l3e);
++        return 0;
++    }
+ 
+     return put_page_and_type_preemptible(l3e_get_page(l3e), preemptible);
+ }
+@@ -1195,7 +1204,17 @@ static int put_page_from_l4e(l4_pgentry_t l4e, unsigned long pfn,
+          (l4e_get_pfn(l4e) != pfn) )
+     {
+         if ( unlikely(partial > 0) )
++        {
++            ASSERT(preemptible >= 0);
+             return __put_page_type(l4e_get_page(l4e), preemptible);
++        }
++
++        if ( preemptible < 0 )
++        {
++            current->arch.old_guest_table = l4e_get_page(l4e);
++            return 0;
++        }
++
+         return put_page_and_type_preemptible(l4e_get_page(l4e), preemptible);
+     }
+     return 1;
+@@ -1485,12 +1504,17 @@ static int alloc_l3_table(struct page_info *page, int preemptible)
+     if ( rc < 0 && rc != -EAGAIN && rc != -EINTR )
+     {
+         MEM_LOG("Failure in alloc_l3_table: entry %d", i);
++        if ( i )
++        {
++            page->nr_validated_ptes = i;
++            page->partial_pte = 0;
++            current->arch.old_guest_table = page;
++        }
+         while ( i-- > 0 )
+         {
+             if ( !is_guest_l3_slot(i) )
+                 continue;
+             unadjust_guest_l3e(pl3e[i], d);
+-            put_page_from_l3e(pl3e[i], pfn, 0, 0);
+         }
+     }
+ 
+@@ -1520,22 +1544,24 @@ static int alloc_l4_table(struct page_info *page, int preemptible)
+             page->nr_validated_ptes = i;
+             page->partial_pte = partial ?: 1;
+         }
+-        else if ( rc == -EINTR )
++        else if ( rc < 0 )
+         {
++            if ( rc != -EINTR )
++                MEM_LOG("Failure in alloc_l4_table: entry %d", i);
+             if ( i )
+             {
+                 page->nr_validated_ptes = i;
+                 page->partial_pte = 0;
+-                rc = -EAGAIN;
++                if ( rc == -EINTR )
++                    rc = -EAGAIN;
++                else
++                {
++                    if ( current->arch.old_guest_table )
++                        page->nr_validated_ptes++;
++                    current->arch.old_guest_table = page;
++                }
+             }
+         }
+-        else if ( rc < 0 )
+-        {
+-            MEM_LOG("Failure in alloc_l4_table: entry %d", i);
+-            while ( i-- > 0 )
+-                if ( is_guest_l4_slot(d, i) )
+-                    put_page_from_l4e(pl4e[i], pfn, 0, 0);
+-        }
+         if ( rc < 0 )
+             return rc;
+ 
+@@ -1965,7 +1991,7 @@ static int mod_l3_entry(l3_pgentry_t *pl3e,
+         pae_flush_pgd(pfn, pgentry_ptr_to_slot(pl3e), nl3e);
+     }
+ 
+-    put_page_from_l3e(ol3e, pfn, 0, 0);
++    put_page_from_l3e(ol3e, pfn, 0, -preemptible);
+     return rc;
+ }
+ 
+@@ -2028,7 +2054,7 @@ static int mod_l4_entry(l4_pgentry_t *pl4e,
+         return -EFAULT;
+     }
+ 
+-    put_page_from_l4e(ol4e, pfn, 0, 0);
++    put_page_from_l4e(ol4e, pfn, 0, -preemptible);
+     return rc;
+ }
+ 
+@@ -2186,7 +2212,15 @@ static int alloc_page_type(struct page_info *page, unsigned long type,
+                 PRtype_info ": caf=%08lx taf=%" PRtype_info,
+                 page_to_mfn(page), get_gpfn_from_mfn(page_to_mfn(page)),
+                 type, page->count_info, page->u.inuse.type_info);
+-        page->u.inuse.type_info = 0;
++        if ( page != current->arch.old_guest_table )
++            page->u.inuse.type_info = 0;
++        else
++        {
++            ASSERT((page->u.inuse.type_info &
++                    (PGT_count_mask | PGT_validated)) == 1);
++            get_page_light(page);
++            page->u.inuse.type_info |= PGT_partial;
++        }
+     }
+     else
+     {
+@@ -2724,49 +2758,150 @@ static void put_superpage(unsigned long mfn)
+ 
+ #endif
+ 
++static int put_old_guest_table(struct vcpu *v)
++{
++    int rc;
++
++    if ( !v->arch.old_guest_table )
++        return 0;
++
++    switch ( rc = put_page_and_type_preemptible(v->arch.old_guest_table, 1) )
++    {
++    case -EINTR:
++    case -EAGAIN:
++        return -EAGAIN;
++    }
++
++    v->arch.old_guest_table = NULL;
++
++    return rc;
++}
++
++int vcpu_destroy_pagetables(struct vcpu *v)
++{
++    unsigned long mfn = pagetable_get_pfn(v->arch.guest_table);
++    struct page_info *page;
++    int rc = put_old_guest_table(v);
++
++    if ( rc )
++        return rc;
++
++#ifdef __x86_64__
++    if ( is_pv_32on64_vcpu(v) )
++        mfn = l4e_get_pfn(*(l4_pgentry_t *)mfn_to_virt(mfn));
++#endif
++
++    if ( mfn )
++    {
++        page = mfn_to_page(mfn);
++        if ( paging_mode_refcounts(v->domain) )
++            put_page(page);
++        else
++            rc = put_page_and_type_preemptible(page, 1);
++    }
++
++#ifdef __x86_64__
++    if ( is_pv_32on64_vcpu(v) )
++    {
++        if ( !rc )
++            l4e_write(
++                (l4_pgentry_t *)__va(pagetable_get_paddr(v->arch.guest_table)),
++                l4e_empty());
++    }
++    else
++#endif
++    if ( !rc )
++    {
++        v->arch.guest_table = pagetable_null();
++
++#ifdef __x86_64__
++        /* Drop ref to guest_table_user (from MMUEXT_NEW_USER_BASEPTR) */
++        mfn = pagetable_get_pfn(v->arch.guest_table_user);
++        if ( mfn )
++        {
++            page = mfn_to_page(mfn);
++            if ( paging_mode_refcounts(v->domain) )
++                put_page(page);
++            else
++                rc = put_page_and_type_preemptible(page, 1);
++        }
++        if ( !rc )
++            v->arch.guest_table_user = pagetable_null();
++#endif
++    }
++
++    v->arch.cr3 = 0;
++
++    return rc;
++}
+ 
+ int new_guest_cr3(unsigned long mfn)
+ {
+     struct vcpu *curr = current;
+     struct domain *d = curr->domain;
+-    int okay;
++    int rc;
+     unsigned long old_base_mfn;
+ 
+ #ifdef __x86_64__
+     if ( is_pv_32on64_domain(d) )
+     {
+-        okay = paging_mode_refcounts(d)
+-            ? 0 /* Old code was broken, but what should it be? */
+-            : mod_l4_entry(
++        rc = paging_mode_refcounts(d)
++             ? -EINVAL /* Old code was broken, but what should it be? */
++             : mod_l4_entry(
+                     __va(pagetable_get_paddr(curr->arch.guest_table)),
+                     l4e_from_pfn(
+                         mfn,
+                         (_PAGE_PRESENT|_PAGE_RW|_PAGE_USER|_PAGE_ACCESSED)),
+-                    pagetable_get_pfn(curr->arch.guest_table), 0, 0, curr) == 0;
+-        if ( unlikely(!okay) )
++                    pagetable_get_pfn(curr->arch.guest_table), 0, 1, curr);
++        switch ( rc )
+         {
++        case 0:
++            break;
++        case -EINTR:
++        case -EAGAIN:
++            return -EAGAIN;
++        default:
+             MEM_LOG("Error while installing new compat baseptr %lx", mfn);
+-            return 0;
++            return rc;
+         }
+ 
+         invalidate_shadow_ldt(curr, 0);
+         write_ptbase(curr);
+ 
+-        return 1;
++        return 0;
+     }
+ #endif
+-    okay = paging_mode_refcounts(d)
+-        ? get_page_from_pagenr(mfn, d)
+-        : !get_page_and_type_from_pagenr(mfn, PGT_root_page_table, d, 0, 0);
+-    if ( unlikely(!okay) )
++    rc = put_old_guest_table(curr);
++    if ( unlikely(rc) )
++        return rc;
++
++    old_base_mfn = pagetable_get_pfn(curr->arch.guest_table);
++    /*
++     * This is particularly important when getting restarted after the
++     * previous attempt got preempted in the put-old-MFN phase.
++     */
++    if ( old_base_mfn == mfn )
+     {
+-        MEM_LOG("Error while installing new baseptr %lx", mfn);
++        write_ptbase(curr);
+         return 0;
+     }
+ 
+-    invalidate_shadow_ldt(curr, 0);
++    rc = paging_mode_refcounts(d)
++         ? (get_page_from_pagenr(mfn, d) ? 0 : -EINVAL)
++         : get_page_and_type_from_pagenr(mfn, PGT_root_page_table, d, 0, 1);
++    switch ( rc )
++    {
++    case 0:
++        break;
++    case -EINTR:
++    case -EAGAIN:
++        return -EAGAIN;
++    default:
++        MEM_LOG("Error while installing new baseptr %lx", mfn);
++        return rc;
++    }
+ 
+-    old_base_mfn = pagetable_get_pfn(curr->arch.guest_table);
++    invalidate_shadow_ldt(curr, 0);
+ 
+     curr->arch.guest_table = pagetable_from_pfn(mfn);
+     update_cr3(curr);
+@@ -2775,13 +2910,25 @@ int new_guest_cr3(unsigned long mfn)
+ 
+     if ( likely(old_base_mfn != 0) )
+     {
++        struct page_info *page = mfn_to_page(old_base_mfn);
++
+         if ( paging_mode_refcounts(d) )
+-            put_page(mfn_to_page(old_base_mfn));
++            put_page(page);
+         else
+-            put_page_and_type(mfn_to_page(old_base_mfn));
++            switch ( rc = put_page_and_type_preemptible(page, 1) )
++            {
++            case -EINTR:
++                rc = -EAGAIN;
++            case -EAGAIN:
++                curr->arch.old_guest_table = page;
++                break;
++            default:
++                BUG_ON(rc);
++                break;
++            }
+     }
+ 
+-    return 1;
++    return rc;
+ }
+ 
+ static struct domain *get_pg_owner(domid_t domid)
+@@ -2910,12 +3057,29 @@ long do_mmuext_op(
+     unsigned int foreigndom)
+ {
+     struct mmuext_op op;
+-    int rc = 0, i = 0, okay;
+     unsigned long type;
+-    unsigned int done = 0;
++    unsigned int i = 0, done = 0;
+     struct vcpu *curr = current;
+     struct domain *d = curr->domain;
+     struct domain *pg_owner;
++    int okay, rc = put_old_guest_table(curr);
++
++    if ( unlikely(rc) )
++    {
++        if ( likely(rc == -EAGAIN) )
++            rc = hypercall_create_continuation(
++                     __HYPERVISOR_mmuext_op, "hihi", uops, count, pdone,
++                     foreigndom);
++        return rc;
++    }
++
++    if ( unlikely(count == MMU_UPDATE_PREEMPTED) &&
++         likely(guest_handle_is_null(uops)) )
++    {
++        /* See the curr->arch.old_guest_table related
++         * hypercall_create_continuation() below. */
++        return (int)foreigndom;
++    }
+ 
+     if ( unlikely(count & MMU_UPDATE_PREEMPTED) )
+     {
+@@ -2940,7 +3104,7 @@ long do_mmuext_op(
+ 
+     for ( i = 0; i < count; i++ )
+     {
+-        if ( hypercall_preempt_check() )
++        if ( curr->arch.old_guest_table || hypercall_preempt_check() )
+         {
+             rc = -EAGAIN;
+             break;
+@@ -3000,21 +3164,17 @@ long do_mmuext_op(
+             page = mfn_to_page(mfn);
+ 
+             if ( (rc = xsm_memory_pin_page(d, page)) != 0 )
+-            {
+-                put_page_and_type(page);
+                 okay = 0;
+-                break;
+-            }
+-
+-            if ( unlikely(test_and_set_bit(_PGT_pinned,
+-                                           &page->u.inuse.type_info)) )
++            else if ( unlikely(test_and_set_bit(_PGT_pinned,
++                                                &page->u.inuse.type_info)) )
+             {
+                 MEM_LOG("Mfn %lx already pinned", mfn);
+-                put_page_and_type(page);
+                 okay = 0;
+-                break;
+             }
+ 
++            if ( unlikely(!okay) )
++                goto pin_drop;
++
+             /* A page is dirtied when its pin status is set. */
+             paging_mark_dirty(pg_owner, mfn);
+            
+@@ -3028,7 +3188,13 @@ long do_mmuext_op(
+                                                &page->u.inuse.type_info));
+                 spin_unlock(&pg_owner->page_alloc_lock);
+                 if ( drop_ref )
+-                    put_page_and_type(page);
++                {
++        pin_drop:
++                    if ( type == PGT_l1_page_table )
++                        put_page_and_type(page);
++                    else
++                        curr->arch.old_guest_table = page;
++                }
+             }
+ 
+             break;
+@@ -3058,7 +3224,17 @@ long do_mmuext_op(
+                 break;
+             }
+ 
+-            put_page_and_type(page);
++            switch ( rc = put_page_and_type_preemptible(page, 1) )
++            {
++            case -EINTR:
++            case -EAGAIN:
++                curr->arch.old_guest_table = page;
++                rc = 0;
++                break;
++            default:
++                BUG_ON(rc);
++                break;
++            }
+             put_page(page);
+ 
+             /* A page is dirtied when its pin status is cleared. */
+@@ -3068,7 +3244,8 @@ long do_mmuext_op(
+         }
+ 
+         case MMUEXT_NEW_BASEPTR:
+-            okay = new_guest_cr3(gmfn_to_mfn(d, op.arg1.mfn));
++            rc = new_guest_cr3(gmfn_to_mfn(d, op.arg1.mfn));
++            okay = !rc;
+             break;
+         
+ #ifdef __x86_64__
+@@ -3076,29 +3253,55 @@ long do_mmuext_op(
+             unsigned long old_mfn, mfn;
+ 
+             mfn = gmfn_to_mfn(d, op.arg1.mfn);
++            old_mfn = pagetable_get_pfn(curr->arch.guest_table_user);
++            /*
++             * This is particularly important when getting restarted after the
++             * previous attempt got preempted in the put-old-MFN phase.
++             */
++            if ( old_mfn == mfn )
++                break;
++
+             if ( mfn != 0 )
+             {
+                 if ( paging_mode_refcounts(d) )
+                     okay = get_page_from_pagenr(mfn, d);
+                 else
+-                    okay = !get_page_and_type_from_pagenr(
+-                        mfn, PGT_root_page_table, d, 0, 0);
++                {
++                    rc = get_page_and_type_from_pagenr(
++                        mfn, PGT_root_page_table, d, 0, 1);
++                    okay = !rc;
++                }
+                 if ( unlikely(!okay) )
+                 {
+-                    MEM_LOG("Error while installing new mfn %lx", mfn);
++                    if ( rc == -EINTR )
++                        rc = -EAGAIN;
++                    else if ( rc != -EAGAIN )
++                        MEM_LOG("Error while installing new mfn %lx", mfn);
+                     break;
+                 }
+             }
+ 
+-            old_mfn = pagetable_get_pfn(curr->arch.guest_table_user);
+             curr->arch.guest_table_user = pagetable_from_pfn(mfn);
+ 
+             if ( old_mfn != 0 )
+             {
++                struct page_info *page = mfn_to_page(old_mfn);
++
+                 if ( paging_mode_refcounts(d) )
+-                    put_page(mfn_to_page(old_mfn));
++                    put_page(page);
+                 else
+-                    put_page_and_type(mfn_to_page(old_mfn));
++                    switch ( rc = put_page_and_type_preemptible(page, 1) )
++                    {
++                    case -EINTR:
++                        rc = -EAGAIN;
++                    case -EAGAIN:
++                        curr->arch.old_guest_table = page;
++                        okay = 0;
++                        break;
++                    default:
++                        BUG_ON(rc);
++                        break;
++                    }
+             }
+ 
+             break;
+@@ -3337,9 +3540,27 @@ long do_mmuext_op(
+     }
+ 
+     if ( rc == -EAGAIN )
++    {
++        ASSERT(i < count);
+         rc = hypercall_create_continuation(
+             __HYPERVISOR_mmuext_op, "hihi",
+             uops, (count - i) | MMU_UPDATE_PREEMPTED, pdone, foreigndom);
++    }
++    else if ( curr->arch.old_guest_table )
++    {
++        XEN_GUEST_HANDLE(void) null;
++
++        ASSERT(rc || i == count);
++        set_xen_guest_handle(null, NULL);
++        /*
++         * In order to have a way to communicate the final return value to
++         * our continuation, we pass this in place of "foreigndom", building
++         * on the fact that this argument isn't needed anymore.
++         */
++        rc = hypercall_create_continuation(
++                __HYPERVISOR_mmuext_op, "hihi", null,
++                MMU_UPDATE_PREEMPTED, null, rc);
++    }
+ 
+     put_pg_owner(pg_owner);
+ 
+@@ -3366,11 +3587,28 @@ long do_mmu_update(
+     void *va;
+     unsigned long gpfn, gmfn, mfn;
+     struct page_info *page;
+-    int rc = 0, okay = 1, i = 0;
+-    unsigned int cmd, done = 0, pt_dom;
+-    struct vcpu *v = current;
++    unsigned int cmd, i = 0, done = 0, pt_dom;
++    struct vcpu *curr = current, *v = curr;
+     struct domain *d = v->domain, *pt_owner = d, *pg_owner;
+     struct domain_mmap_cache mapcache;
++    int rc = put_old_guest_table(curr), okay = 1;
++
++    if ( unlikely(rc) )
++    {
++        if ( likely(rc == -EAGAIN) )
++            rc = hypercall_create_continuation(
++                     __HYPERVISOR_mmu_update, "hihi", ureqs, count, pdone,
++                     foreigndom);
++        return rc;
++    }
++
++    if ( unlikely(count == MMU_UPDATE_PREEMPTED) &&
++         likely(guest_handle_is_null(ureqs)) )
++    {
++        /* See the curr->arch.old_guest_table related
++         * hypercall_create_continuation() below. */
++        return (int)foreigndom;
++    }
+ 
+     if ( unlikely(count & MMU_UPDATE_PREEMPTED) )
+     {
+@@ -3419,7 +3657,7 @@ long do_mmu_update(
+ 
+     for ( i = 0; i < count; i++ )
+     {
+-        if ( hypercall_preempt_check() )
++        if ( curr->arch.old_guest_table || hypercall_preempt_check() )
+         {
+             rc = -EAGAIN;
+             break;
+@@ -3684,9 +3922,27 @@ long do_mmu_update(
+     }
+ 
+     if ( rc == -EAGAIN )
++    {
++        ASSERT(i < count);
+         rc = hypercall_create_continuation(
+             __HYPERVISOR_mmu_update, "hihi",
+             ureqs, (count - i) | MMU_UPDATE_PREEMPTED, pdone, foreigndom);
++    }
++    else if ( curr->arch.old_guest_table )
++    {
++        XEN_GUEST_HANDLE(void) null;
++
++        ASSERT(rc || i == count);
++        set_xen_guest_handle(null, NULL);
++        /*
++         * In order to have a way to communicate the final return value to
++         * our continuation, we pass this in place of "foreigndom", building
++         * on the fact that this argument isn't needed anymore.
++         */
++        rc = hypercall_create_continuation(
++                __HYPERVISOR_mmu_update, "hihi", null,
++                MMU_UPDATE_PREEMPTED, null, rc);
++    }
+ 
+     put_pg_owner(pg_owner);
+ 
+diff --git a/xen/arch/x86/traps.c b/xen/arch/x86/traps.c
+index 234d9ac..e336439 100644
+--- a/xen/arch/x86/traps.c
++++ b/xen/arch/x86/traps.c
+@@ -2317,8 +2317,15 @@ static int emulate_privileged_op(struct cpu_user_regs *regs)
+                 rc = new_guest_cr3(gmfn_to_mfn(v->domain, compat_cr3_to_pfn(*reg)));
+ #endif
+             domain_unlock(v->domain);
+-            if ( rc == 0 ) /* not okay */
++            switch ( rc )
++            {
++            case 0:
++                break;
++            case -EAGAIN: /* retry after preemption */
++                goto skip;
++            default:      /* not okay */
+                 goto fail;
++            }
+             break;
+ 
+         case 4: /* Write CR4 */
+diff --git a/xen/arch/x86/x86_64/compat/mm.c b/xen/arch/x86/x86_64/compat/mm.c
+index 3ef08a5..6ad41d4 100644
+--- a/xen/arch/x86/x86_64/compat/mm.c
++++ b/xen/arch/x86/x86_64/compat/mm.c
+@@ -222,6 +222,13 @@ int compat_mmuext_op(XEN_GUEST_HANDLE(mmuext_op_compat_t) cmp_uops,
+     int rc = 0;
+     XEN_GUEST_HANDLE(mmuext_op_t) nat_ops;
+ 
++    if ( unlikely(count == MMU_UPDATE_PREEMPTED) &&
++         likely(guest_handle_is_null(cmp_uops)) )
++    {
++        set_xen_guest_handle(nat_ops, NULL);
++        return do_mmuext_op(nat_ops, count, pdone, foreigndom);
++    }
++
+     preempt_mask = count & MMU_UPDATE_PREEMPTED;
+     count ^= preempt_mask;
+ 
+@@ -319,17 +326,23 @@ int compat_mmuext_op(XEN_GUEST_HANDLE(mmuext_op_compat_t) cmp_uops,
+                                     : mcs->call.args[1];
+                 unsigned int left = arg1 & ~MMU_UPDATE_PREEMPTED;
+ 
+-                BUG_ON(left == arg1);
++                BUG_ON(left == arg1 && left != i);
+                 BUG_ON(left > count);
+                 guest_handle_add_offset(nat_ops, i - left);
+                 guest_handle_subtract_offset(cmp_uops, left);
+                 left = 1;
+-                BUG_ON(!hypercall_xlat_continuation(&left, 0x01, nat_ops, cmp_uops));
+-                BUG_ON(left != arg1);
+-                if (!test_bit(_MCSF_in_multicall, &mcs->flags))
+-                    regs->_ecx += count - i;
++                if ( arg1 != MMU_UPDATE_PREEMPTED )
++                {
++                    BUG_ON(!hypercall_xlat_continuation(&left, 0x01, nat_ops,
++                                                        cmp_uops));
++                    if ( !test_bit(_MCSF_in_multicall, &mcs->flags) )
++                        regs->_ecx += count - i;
++                    else
++                        mcs->compat_call.args[1] += count - i;
++                }
+                 else
+-                    mcs->compat_call.args[1] += count - i;
++                    BUG_ON(hypercall_xlat_continuation(&left, 0));
++                BUG_ON(left != arg1);
+             }
+             else
+                 BUG_ON(err > 0);
+diff --git a/xen/common/compat/domain.c b/xen/common/compat/domain.c
+index 67e0e5e..5fe393f 100644
+--- a/xen/common/compat/domain.c
++++ b/xen/common/compat/domain.c
+@@ -52,6 +52,10 @@ int compat_vcpu_op(int cmd, int vcpuid, XEN_GUEST_HANDLE(void) arg)
+             rc = boot_vcpu(d, vcpuid, cmp_ctxt);
+         domain_unlock(d);
+ 
++        if ( rc == -EAGAIN )
++            rc = hypercall_create_continuation(__HYPERVISOR_vcpu_op, "iih",
++                                               cmd, vcpuid, arg);
++
+         xfree(cmp_ctxt);
+         break;
+     }
+diff --git a/xen/common/domain.c b/xen/common/domain.c
+index 054f7c4..5fa045b 100644
+--- a/xen/common/domain.c
++++ b/xen/common/domain.c
+@@ -770,14 +770,18 @@ int boot_vcpu(struct domain *d, int vcpuid, vcpu_guest_context_u ctxt)
+     return arch_set_info_guest(v, ctxt);
+ }
+ 
+-void vcpu_reset(struct vcpu *v)
++int vcpu_reset(struct vcpu *v)
+ {
+     struct domain *d = v->domain;
++    int rc;
+ 
+     vcpu_pause(v);
+     domain_lock(d);
+ 
+-    arch_vcpu_reset(v);
++    set_bit(_VPF_in_reset, &v->pause_flags);
++    rc = arch_vcpu_reset(v);
++    if ( rc )
++        goto out_unlock;
+ 
+     set_bit(_VPF_down, &v->pause_flags);
+ 
+@@ -793,9 +797,13 @@ void vcpu_reset(struct vcpu *v)
+ #endif
+     cpus_clear(v->cpu_affinity_tmp);
+     clear_bit(_VPF_blocked, &v->pause_flags);
++    clear_bit(_VPF_in_reset, &v->pause_flags);
+ 
++ out_unlock:
+     domain_unlock(v->domain);
+     vcpu_unpause(v);
++
++    return rc;
+ }
+ 
+ 
+@@ -834,6 +842,11 @@ long do_vcpu_op(int cmd, int vcpuid, XEN_GUEST_HANDLE(void) arg)
+         domain_unlock(d);
+ 
+         xfree(ctxt);
++
++        if ( rc == -EAGAIN )
++            rc = hypercall_create_continuation(__HYPERVISOR_vcpu_op, "iih",
++                                               cmd, vcpuid, arg);
++
+         break;
+ 
+     case VCPUOP_up:
+diff --git a/xen/common/domctl.c b/xen/common/domctl.c
+index 981cb1a..faac366 100644
+--- a/xen/common/domctl.c
++++ b/xen/common/domctl.c
+@@ -286,8 +286,10 @@ long do_domctl(XEN_GUEST_HANDLE(xen_domctl_t) u_domctl)
+ 
+         if ( guest_handle_is_null(op->u.vcpucontext.ctxt) )
+         {
+-            vcpu_reset(v);
+-            ret = 0;
++            ret = vcpu_reset(v);
++            if ( ret == -EAGAIN )
++                ret = hypercall_create_continuation(
++                          __HYPERVISOR_domctl, "h", u_domctl);
+             goto svc_out;
+         }
+ 
+@@ -316,6 +318,10 @@ long do_domctl(XEN_GUEST_HANDLE(xen_domctl_t) u_domctl)
+             domain_pause(d);
+             ret = arch_set_info_guest(v, c);
+             domain_unpause(d);
++
++            if ( ret == -EAGAIN )
++                ret = hypercall_create_continuation(
++                          __HYPERVISOR_domctl, "h", u_domctl);
+         }
+ 
+     svc_out:
+diff --git a/xen/include/asm-x86/domain.h b/xen/include/asm-x86/domain.h
+index fe1459d..a387862 100644
+--- a/xen/include/asm-x86/domain.h
++++ b/xen/include/asm-x86/domain.h
+@@ -405,6 +405,7 @@ struct arch_vcpu
+     pagetable_t guest_table_user;       /* (MFN) x86/64 user-space pagetable */
+ #endif
+     pagetable_t guest_table;            /* (MFN) guest notion of cr3 */
++    struct page_info *old_guest_table;  /* partially destructed pagetable */
+     /* guest_table holds a ref to the page, and also a type-count unless
+      * shadow refcounts are in use */
+     pagetable_t shadow_table[4];        /* (MFN) shadow(s) of guest */
+diff --git a/xen/include/asm-x86/mm.h b/xen/include/asm-x86/mm.h
+index c93a022..2498007 100644
+--- a/xen/include/asm-x86/mm.h
++++ b/xen/include/asm-x86/mm.h
+@@ -554,6 +554,7 @@ void audit_domains(void);
+ int new_guest_cr3(unsigned long pfn);
+ void make_cr3(struct vcpu *v, unsigned long mfn);
+ void update_cr3(struct vcpu *v);
++int vcpu_destroy_pagetables(struct vcpu *);
+ void propagate_page_fault(unsigned long addr, u16 error_code);
+ void *do_page_walk(struct vcpu *v, unsigned long addr);
+ 
+diff --git a/xen/include/xen/domain.h b/xen/include/xen/domain.h
+index edffd1f..5175ef7 100644
+--- a/xen/include/xen/domain.h
++++ b/xen/include/xen/domain.h
+@@ -15,7 +15,7 @@ struct vcpu *alloc_vcpu(
+ int boot_vcpu(
+     struct domain *d, int vcpuid, vcpu_guest_context_u ctxt);
+ struct vcpu *alloc_dom0_vcpu0(void);
+-void vcpu_reset(struct vcpu *v);
++int vcpu_reset(struct vcpu *);
+ 
+ struct xen_domctl_getdomaininfo;
+ void getdomaininfo(struct domain *d, struct xen_domctl_getdomaininfo *info);
+@@ -57,7 +57,7 @@ void arch_dump_vcpu_info(struct vcpu *v);
+ 
+ void arch_dump_domain_info(struct domain *d);
+ 
+-void arch_vcpu_reset(struct vcpu *v);
++int arch_vcpu_reset(struct vcpu *);
+ 
+ bool_t domctl_lock_acquire(void);
+ void domctl_lock_release(void);
+diff --git a/xen/include/xen/sched.h b/xen/include/xen/sched.h
+index 35c3a7f..c04b25d 100644
+--- a/xen/include/xen/sched.h
++++ b/xen/include/xen/sched.h
+@@ -592,6 +592,9 @@ extern struct domain *domain_list;
+  /* VCPU is blocked on memory-event ring. */
+ #define _VPF_mem_event       4
+ #define VPF_mem_event        (1UL<<_VPF_mem_event)
++ /* VCPU is being reset. */
++#define _VPF_in_reset        7
++#define VPF_in_reset         (1UL<<_VPF_in_reset)
+ 
+ static inline int vcpu_runnable(struct vcpu *v)
+ {
diff --git a/main/xen/xsa58-4.1.patch b/main/xen/xsa58-4.1.patch
new file mode 100644
index 0000000000..3c982a35e0
--- /dev/null
+++ b/main/xen/xsa58-4.1.patch
@@ -0,0 +1,119 @@
+x86: fix page refcount handling in page table pin error path
+
+In the original patch 7 of the series addressing XSA-45 I mistakenly
+took the addition of the call to get_page_light() in alloc_page_type()
+to cover two decrements that would happen: One for the PGT_partial bit
+that is getting set along with the call, and the other for the page
+reference the caller hold (and would be dropping on its error path).
+But of course the additional page reference is tied to the PGT_partial
+bit, and hence any caller of a function that may leave
+->arch.old_guest_table non-NULL for error cleanup purposes has to make
+sure a respective page reference gets retained.
+
+Similar issues were then also spotted elsewhere: In effect all callers
+of get_page_type_preemptible() need to deal with errors in similar
+ways. To make sure error handling can work this way without leaking
+page references, a respective assertion gets added to that function.
+
+This is CVE-2013-1432 / XSA-58.
+
+Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
+Signed-off-by: Jan Beulich <jbeulich@suse.com>
+Tested-by: Andrew Cooper <andrew.cooper3@citrix.com>
+Reviewed-by: Tim Deegan <tim@xen.org>
+
+--- a/xen/arch/x86/domain.c
++++ b/xen/arch/x86/domain.c
+@@ -798,6 +798,10 @@ int arch_set_info_guest(
+     if ( v->vcpu_id == 0 )
+         d->vm_assist = c(vm_assist);
+ 
++    rc = put_old_guest_table(current);
++    if ( rc )
++        return rc;
++
+     if ( !compat )
+         rc = (int)set_gdt(v, c.nat->gdt_frames, c.nat->gdt_ents);
+ #ifdef CONFIG_COMPAT
+@@ -840,18 +844,24 @@ int arch_set_info_guest(
+     }
+     else
+     {
+-        /*
+-         * Since v->arch.guest_table{,_user} are both NULL, this effectively
+-         * is just a call to put_old_guest_table().
+-         */
+         if ( !compat )
+-            rc = vcpu_destroy_pagetables(v);
++            rc = put_old_guest_table(v);
+         if ( !rc )
+             rc = get_page_type_preemptible(cr3_page,
+                                            !compat ? PGT_root_page_table
+                                                    : PGT_l3_page_table);
+-        if ( rc == -EINTR )
++        switch ( rc )
++        {
++        case -EINTR:
+             rc = -EAGAIN;
++        case -EAGAIN:
++        case 0:
++            break;
++        default:
++            if ( cr3_page == current->arch.old_guest_table )
++                cr3_page = NULL;
++            break;
++        }
+     }
+ 
+     if ( rc )
+@@ -883,6 +893,11 @@ int arch_set_info_guest(
+                         pagetable_get_page(v->arch.guest_table);
+                     v->arch.guest_table = pagetable_null();
+                     break;
++                default:
++                    if ( cr3_page == current->arch.old_guest_table )
++                        cr3_page = NULL;
++                case 0:
++                    break;
+                 }
+             }
+ 
+--- a/xen/arch/x86/mm.c
++++ b/xen/arch/x86/mm.c
+@@ -682,7 +682,8 @@ static int get_page_and_type_from_pagenr
+           get_page_type_preemptible(page, type) :
+           (get_page_type(page, type) ? 0 : -EINVAL));
+ 
+-    if ( unlikely(rc) && partial >= 0 )
++    if ( unlikely(rc) && partial >= 0 &&
++         (!preemptible || page != current->arch.old_guest_table) )
+         put_page(page);
+ 
+     return rc;
+@@ -2555,6 +2556,7 @@ int put_page_type_preemptible(struct pag
+ 
+ int get_page_type_preemptible(struct page_info *page, unsigned long type)
+ {
++    ASSERT(!current->arch.old_guest_table);
+     return __get_page_type(page, type, 1);
+ }
+ 
+@@ -2765,7 +2767,7 @@ static void put_superpage(unsigned long 
+ 
+ #endif
+ 
+-static int put_old_guest_table(struct vcpu *v)
++int put_old_guest_table(struct vcpu *v)
+ {
+     int rc;
+ 
+--- a/xen/include/asm-x86/mm.h
++++ b/xen/include/asm-x86/mm.h
+@@ -337,6 +337,7 @@ void put_page_type(struct page_info *pag
+ int  get_page_type(struct page_info *page, unsigned long type);
+ int  put_page_type_preemptible(struct page_info *page);
+ int  get_page_type_preemptible(struct page_info *page, unsigned long type);
++int  put_old_guest_table(struct vcpu *);
+ int  get_page_from_l1e(
+     l1_pgentry_t l1e, struct domain *l1e_owner, struct domain *pg_owner);
+ void put_page_from_l1e(l1_pgentry_t l1e, struct domain *l1e_owner);